I need some advise

My little boy is turning 2 next month and about 7 months ago I noticed a lump on his neck... The lump has gotten a little bigger but not much... I have been taking him to the doctors and he keeps telling me he is fine that its just viral... I don't believe that's the case.. He had blood work done it came back normal he has had an ultrasound done not sure the results yet.. Last week I noticed another small lump under his chin in his neckI... As anyone gone through the same thing? What's your story..